Dual hand truck

Abstract

A dual position hand truck includes a central frame having two side rails and a toe plate. Positioned at an upper end of the central frame is a U-shaped handle bar which has a hand gripping portion and two extended legs with castered wheels attached at their respective bottom ends. The handle bar is pivotally attached to the frame by a fixed shaft and a pair of support brackets. The support brackets also allow the extended legs to slide along their length. Attached to the support brackets is a spring biased locking bar which locks the handle bar against rotational movement relative to the frame.

What is claimed is:  
     
       1. A dual position hand truck which converts from a two-wheeled version to a four-wheeled platform truck comprising: 
       a pair of side rails having upper and lower ends joined by cross rails along their length and a toe plate for load supporting in the two wheel configuration joining the lower ends of the side rails;  
       an axle supporting a pair of wheels attached at the lower end of the side rails;  
       a U-shaped handle bar having a pair of extended parallel legs pivotally attached to the side rails at their upper ends;  
       a pair of castered wheels mounted on the ends of said legs for use in the four-wheeled platform version;  
       a pair of support brackets each bracket being pivotally mounted on a side rail, each bracket supporting one of said legs for sliding movement therein and rotational movement relative to the side rails;  
       at least one latch plate mounted on one of said rails having at least two latching positions for rotational locking of said legs;  
       a locking bar rotatably mounted on said support bracket for engaging the two latching positions on the latch plate and locking the legs of the handle bar in at least two angular positions;  
       at least one locking pin mounted on said support bracket for engaging one of said legs and preventing the handle bar from sliding movement in the support bracket, the locking pin being actuated by movement of said locking bar.  
     
     
       2. A dual position hand truck, as set forth in claim  1 , wherein the locking bar includes a pair of arms normally positioned relative to the locking bar and a pair of pivot pins, each pin being mounted on one of said arms and offset from the locking bar, each pin being pivotally journaled in one of said support brackets to permit engagement of the latch plate in said latching positions. 
     
     
       3. A dual position hand truck, as set forth in claim  1  wherein there are two latch plates, each being mounted on the upper end of a side rail, the latching positions of each latch plate comprising at least two notches which can be releasably engaged by said locking bar. 
     
     
       4. A dual position hand truck, as set forth in claim  1 , wherein the locking bar includes a pair of arms normally positioned relative to the locking bar and a pair of pivot pins, each pin being mounted on one of said arms and offset from the locking bar, each pin being pivotally journaled in one of said support brackets to permit engagement of the latch plate in said latching positions and the locking pins are each mounted on an arm which in turn is integral with one of said pivot pins whereby rotation of the locking bar also releasably engages the locking pins from the legs of the handle bar. 
     
     
       5. A dual position hand truck, as set forth in claim  1  wherein there are two latch plates, each being mounted on the upper end of a side rail, the latching positions of each latch plate comprising at least two notches which can be releasably engaged by said locking bar and the latch plates include an arcuate surface between the two notches and the locking pin is actuated by rotation of the locking bar which is spring biased against the arcuate surfaces. 
     
     
       6. A dual position hand truck, as set forth in claim  1 , wherein the locking bar includes a pair of arms normally positioned relative to the locking bar and a pair of pivot pins, each pin being mounted on one of said arms and offset from the locking bar with the pins lying longitudinally parallel to the locking bar, with each pin being pivotally journaled in a support bracket to permit releasable engagement of the locking bar in at least two latching positions. 
     
     
       7. A dual position hand truck, as set forth in claim  1 , wherein the two latching positions on the latch plate provide 90-degree rotation of the handle bar legs with one position of the legs lying parallel and juxtaposed to the side rails. 
     
     
       8. A dual position hand truck, as set forth in claim  1 , wherein there are two latch plates, each mounted on the upper end of said side rails, the two latching positions comprise radial notches in the latch plates spaced substantially 90 degrees apart for engagement by said locking bar.